As a vehicle door lock device, there is a vehicle door lock device disclosed in, for example, Patent Literature 1. This vehicle door lock device includes a housing having an opening and being configured to be assembled to a door of a vehicle, a coupling member having a coupling portion and being configured to be coupled to an operation mechanism arranged on the door, an operation lever being arranged inside the housing and having a coupling portion coupled to the coupling portion of the coupling member through the opening, and a cover openable and closable so as to expose and hide the opening and a coupling point between the coupling member and the operation lever.